A cast web formed on a support in a casting process is peeled off the support by a first roller in a peeling and conveying process. As being peeled by the first roller, the cast web forms a film, and conveyed through a second roller to a tenter drying process. The peeling and conveying process has a length from a peeling position to a holding position of the film by clips. The length is set to be 10% to 80% of the width of the cast web. The first and second rollers are concave rollers. A couple of blowers are disposed at the end of the peeling and conveying process, to blow the lateral sides of the film in laterally outward directions of the film, to stretch curls in the lateral sides of the film.